In today's highly sophisticated, complex and intelligent industrial automation systems, RFID (Radio Frequency Identification) technology is becoming an increasingly important presence for logistics concerns, material handling and inventory management. Simply knowing that an object exists in a large warehouse is no longer sufficient. When implementing an RFID solution in a distribution center or a factory, it is customary to utilize three distinct platforms: an RFID reader/antenna (e.g., a fixed implementation), RFID “middleware” software running on a standard PC (Personal Computer), and an industrial controller (e.g., a PLC-Programmable Logic Controller). A traditional communications approach is to have the RFID reader connect to the controller via a network using, for example, RS-232 serial communications, Ethernet, or any of the field buses such as DeviceNet, ControlNet, etc.
The value to a company in knowing the location of the reader can be used to improve manufacturing and distribution efficiency, which translates to a more effective competitive presence in the marketplace. In conventional RFID implementations, the physical location of the RFID reader is usually provided by the human operator, or readers are fixed at known locations such that RFID-tagged material that passes within range of the reader can be read and its location determined based on the location of the reader. However, given the rapid technological advances in portable handheld communications devices (e.g., cell phones and PDAs), customers are demanding such portability in RFID readers.
When a mobile RFID reader is utilized for reading RFID tags on objects in a distribution center or a factory, a computer that captures the data from such a reader is utilized to relate the data to the known reader location for determining the approximate location of the tagged object. However, the small and portable RFID reader can now be a mobile handheld device, and also mounted on forklift trucks, AGVs (Automated Guided Vehicles) and/or LGVs (Laser Guided Vehicles), and other mobile means in a warehouse or a factory further exacerbating the difficulty in determining the reader location at a given point in time. Accordingly, there is an unmet need in the art for an improved mobile reader location determination mechanism.